In a CMOS camera, images are read-out using a clock, which switches the multiplexer from one pixel to another, reading a voltage value after a fixed integration interval. Images are therefore produced by sequentially scanning the array using column and row scanners. Once the image is captured further signal processing can be performed by first buffering the entire frame before processing each pixel value sequentially. The cameras have significantly influenced the way we store and process image information in a matrix form. This format is simple and practical for image storage, but it is not ideal for image processing and feature-extraction. The reason is that intensity-based images contain a very high level of redundancy. Pixel intensity is useful for human interpretation and retrieval, but is a burden for machine-based processing. Therefore, there may be a need for efficient image sensors.